Dispenser, a pump engine for a dispenser and a container for a dispenser

ABSTRACT

A pump engine or unit for pump-action fluid dispenser has a fluid storage chamber ( 16 ), a final fluid outlet nozzle and a manually actuated pump for delivering fluid from the fluid storage chamber to the outlet under pressure. The engine has a body comprising two parts ( 48, 50 ) which define between them the fluid storage chamber and least one chamber ( 64 ) of the pump. The fluid storage chamber is defined between opposing wall portions ( 52, 54 ) of the two parts of the body and at least one of the opposing wall portions ( 54 ) is flexible and is configured to conform closely to the contour of the other of the opposing wall portions ( 52 ), at least when the fluid storage chamber is empty.

This invention relates to fluid dispensers. More particularly but not exclusively, this invention relates to dispensers that incorporate a mechanical pump and nozzle arrangement for dispensing fluid under pressure in the form of a spray or a bolus of liquid or as foam and to methods of making the same. The invention also relates to a pump engine and a fluid container for use with a dispenser.

Dispensers that incorporate a mechanical pump and nozzle arrangement are commonly used to provide a means by which fluids can be dispensed from a non-pressurised container, or other fluid source, in the form of a spray, a bolus of liquid or as a foam. Such dispensers are often referred to as pump-action dispensers.

Conventional pump-action dispensers typically comprise a pump mechanism having at least one pump chamber into which a fluid can be drawn from a fluid source and means operative to reduce the volume of the chamber to pressurise the fluid therein. The known pump mechanisms incorporate an outlet valve arrangement that allows the fluid in the chamber to pass from the chamber into a nozzle only once it has reached a predetermined pressure. The fluid then passes through the nozzle to an outlet from which it issues as a spray, bolus or foam. In some known pump-action dispensers, a trigger actuator is provided which can be pulled or pushed by a user to actuate the pump mechanism. Such pump-action dispensers are sometimes referred to as trigger dispensers. Alternatively, it is known to provide a pump-action dispenser with an actuation member that is depressed by a user to actuate the pump mechanism.

Conventional pump-action dispensers tend to be extremely complex in design and typically comprise numerous component parts. As a consequence, these dispensers can be extremely costly to manufacture due to the amount of material required to form the individual components and the assembly processes involved.

A further problem with many of the conventional pump-action dispensers is that they will not function repeatedly when inverted. This is because a fresh charge of fluid must be drawn into the pump chamber after each use. Typically, the fluid is drawn into the chamber through a dip tube that extends into the fluid source. To ensure that all, or at least most, of the fluid in the source can be dispensed, the dip tube usually extends down towards the base of the fluid source. However, if the fluid source is not completely full, the open end of the dip tube will be exposed above the level of the fluid when the dispenser is inverted so that the chamber cannot be refilled.

A further limitation of known pump-action dispensers is that the amount of fluid dispensed on each actuation may vary as it cannot be guaranteed that the chamber will be fully charged with the product to be dispensed each time. This makes pump-action dispensers unsuitable for use in dispensing medicinal products that require accurate dosing.

A further limitation of known pump-action dispensers is that the pump-mechanism and nozzle tends to be bulky, which increases the raw material costs. Where the pump mechanism and nozzle are removeably connected to a container forming the fluid source, all or part of the pump mechanism is often disposed inside the container. This is a further drawback because it reduces the internal volume of the container available for storing fluid, which can be a particular problem with small containers where the available space inside the container is limited. Equally, where the container is small or has a narrow neck, the size of the pump mechanism is correspondingly limited and this limits the amount of pressure that can be generated by the dispenser as well as the volume of fluid that can be dispensed, and, for this reason, can be detrimental to the performance of the dispenser.

A further problem with known pump-action dispensers is the difficulty of varying the external appearance to provide the consumer with an attractive range of products. Typically, the working components of the dispenser are housed in a body which forms the outer surface dispenser and which is visible to the end user. Thus even small changes in the external appearance require whole dispenser to be re-designed and new tooling manufactured.

There is a need, therefore, for a dispenser that overcomes, or at least mitigates, some or all of the above disadvantages of the known dispensers.

In accordance with a first aspect of the invention, there is provided a pump engine for pump-action fluid dispenser, the engine comprising a fluid storage chamber, a fluid outlet and a manually actuated pump means for delivering fluid from the fluid storage chamber to the outlet under pressure, the engine having a body comprising two parts which define between them the fluid storage chamber and least one pump chamber of the pump means, characterised in that the fluid storage chamber is defined between opposing wall portions of the two parts of the body and in that at least one of the opposing wall portions is flexible and is configured to conform closely to the contour of the other of the opposing wall portions, at least when the fluid storage chamber is empty.

The other of the opposing wall portions may be rigid and may have an inner surface which is generally concave.

The flexible wall portion may be resiliently biased to conform closely to the contour of the other of the opposing wall portions.

The fluid storage chamber may have an inlet through which fluid can be introduced into the chamber. The inlet may have a closure means that can be removed to allow the chamber to be refilled.

The pump may comprise a first pump chamber having an inlet fluidly connected to the fluid storage chamber through which a first fluid in the fluid storage chamber can enter the first pump chamber, and an outlet fluidly connected by means of a first fluid passage means to the fluid outlet, the pump further comprising one way valve means configured to permit fluid to enter the first chamber through the inlet from the fluid storage chamber only when the pressure in the first pump chamber is at a predetermined threshold value that is lower than the pressure of the first fluid in the fluid storage chamber and an outlet pre-compression valve means configured to permit fluid to pass from the first pump chamber through the first fluid passage means to the fluid outlet only when the fluid in the chamber is at or above a predetermined threshold value.

The pump may further comprise a second pump chamber for delivering a second fluid to the fluid outlet under pressure and having an inlet means through which the second fluid can enter the second pump chamber from a second fluid source, the inlet having a one way valve means arranged to permit fluid from the second fluid source to enter the second fluid chamber only when the pressure within the second chamber is below that of the fluid in the second fluid source and an outlet fluidly connected to fluid outlet by means of a second fluid passage means, the pump engine further comprising a second fluid pre-compression valve arranged to permit the second fluid to flow from the second pump chamber through the second passage means only when the second fluid in the second chamber is at, or above, a predetermined minimum value.

The second fluid source may comprise a further fluid storage chamber in the engine which may be defined between opposing wall portions of the two parts of the body, at least one of the opposing wall portions being flexible and configured to conform closely to the other of the opposing wall portions, at least when the further fluid storage chamber is empty.

The second fluid may be air, in which case the second pump chamber inlet may be configured to enable ambient air to be drawn into the second pump chamber when the pressure inside the second pump chamber is at or below the ambient air pressure.

In one embodiment, the first fluid is a liquid and the first fluid passage includes a mixing chamber, the second fluid passage means fluidly connecting the outlet of the second pump chamber with the mixing chamber, the engine further comprising a third fluid passage means which fluidly connects the outlet of the second pump chamber with the first passage means at a position upstream from the mixing chamber, the arrangement being such that in use, the air flowing from the second chamber is divided into two portions, one portion flowing through the second fluid passage means directly into the mixing chamber to mix with the liquid flowing from the first pump chamber, and a second portion, which flows through the third fluid passage means into the first passage to assist in driving the liquid along the first fluid passage means into the mixing chamber.

The first fluid passage means may include a pre-compression chamber immediately downstream of the first pump chamber outlet pre-compression valve, and the third fluid passage means may fluidly connect the outlet of the second pump chamber with the first pump chamber outlet pre-compression chamber.

The first pump chamber may be defined between a flexible member and a rigid wall portion of the engine, and the flexible member may be compressible towards the rigid wall portion to pressurise the fluid in the first chamber. The flexible member may be a dome-shaped member

The second pump chamber may be defined in part by means of a further flexible member which can be compressed or distorted to reduce the volume of the second chamber so as to pressurise the fluid inside the second chamber. The further flexible member may be a rolling diaphragm.

The engine may consist of two members that are assembled together to form the engine.

One of the members may comprise a rigid frame to which all the flexible components of the engine are mounted and the other of the members may be formed entirely of a substantially rigid material.

Said one of the members may be formed from two or more plastics materials using bi-injection moulding techniques.

The two members may be moulded as a single integral component with the two members joined to one another by flexible hinge means so that they can be moved relative to one another for assembly.

The two members may be permanently fixed together in the assembled condition by welding.

The final outlet may comprise an outlet nozzle and the dispenser may be configured to dispense a liquid as an atomised spray.

The engine may be configured to dispense a set dose of fluid on each actuation.

In accordance with a second aspect of the invention, there is provided a pump-action dispenser comprising an engine according to the first aspect, the dispenser further comprising an actuator member to which a user can apply a force to actuate the pump means.

The actuator member may be configured to engage and compress the flexible member and the further flexible member when a force is applied by a user.

The first and second pump chambers may be laterally spaced from one another, and the actuator member may have two abutment means configured so that when a force is applied by a user, a first one of the abutment means contacts and compresses the flexible member defining the first pump chamber and a second one of the abutment means contacts and compresses the flexible member defining the second pump chamber.

The dispenser may be configured so that the second abutment means contacts and compresses the flexible member defining the second pump chamber to pressurise the fluid in the second chamber before first abutment means contacts and compresses the flexible member defining the first pump chamber.

The dispenser may be configured so that, in use when a user applies a force to the actuator member, the flexible member defining the second pump chamber continues to be compressed for a short period after the flexible member defining the first pump chamber is fully compressed.

The actuator member may be configured to rock, tilt, deform or distort after the flexible member defining the first pump chamber has been fully compressed so as to continue compressing the flexible member defining the second pump chamber.

The actuator may be formed integrally with or mounted to the engine.

In accordance with a third aspect of the invention, there is provided a pump-action dispenser comprising a pump engine in accordance with the first aspect of the invention and an outer casing which covers at least part of the engine.

The outer casing may completely encase the pump engine and may have an opening which corresponds with the fluid outlet of the engine.

The engine may be removably mounted to the outer casing so that the engine can be removed from the outer casing and replaced by a similar engine.

In accordance with a fourth aspect of the invention, there is provided a dispenser in accordance with both the second and third aspects of the invention, in which the actuator member comprises part of the outer casing.

The actuator member may be an integral part of a wall portion of the outer casing and may be attached to the wall portion by means of a flexible hinge.

In accordance with a fifth aspect of the invention, there is provided a fluid container for a pump-action dispenser, the container having a chamber for receiving a fluid to be dispensed, characterised in that the chamber is defined between a rigid wall portion of the container and a flexible wall portion of the container that is configured to conform closely to the contour of the rigid wall portion, at least when the container is empty.

The flexible wall portion may be resiliently biased to conform closely to the contour of the rigid wall portion which may have an inner surface that defines a generally concave recess.

In accordance with a sixth aspect of the invention, there is provided a pump-action dispenser having a fluid container in accordance with the fifth aspect of the invention.

In accordance with a seventh aspect of the invention, there is provided a pump-action fluid dispenser, the dispenser comprising a pump chamber at least partly defined by a flexibly resilient rolling diaphragm.

The pump chamber may be defined between the rolling diaphragm and a rigid wall portion.

In accordance with an eighth aspect of the invention, there is provided a pump-action fluid dispenser comprising an outlet nozzle, a first pump chamber for pressurising a liquid to be dispensed, a second pump chamber for pressurising air, a first fluid passage means for fluidly connecting the first chamber to the outlet nozzle, a second fluid passage means for fluidly connecting the second pump chamber to a mixing chamber forming part of the first passage means; characterised in that the dispenser further comprises a third fluid passage means for connecting the second chamber to the first fluid passage means at a position upstream from the mixing chamber.

The mixing chamber may be an expansion chamber having a cross sectional area larger than that of the fluid passageways leading into it and may be located upstream of the outlet nozzle.

The dispenser may be configured to dispense the liquid in the form of an atomised spray and the outlet nozzle may comprise one or more control means configured to affect the quality of the spray.

The control means may comprise one or more selected from the following group: a swirl chamber; an expansion chamber; an inner orifice configured to generate a spray or jet of the liquid inside the nozzle; a dog leg; or multiple flow passageways.

In accordance with a ninth aspect of the invention, there is provided a pump-action fluid dispenser comprising an outlet nozzle, a first pump chamber for pressurising a liquid to be dispensed, a second pump chamber for pressurising air, a first fluid passage means for fluidly connecting the first chamber to the outlet nozzle, a second fluid passage means for fluidly connecting the second pump chamber to a mixing chamber forming part of the first passage means, characterised in that the dispenser is configured such that during use when the pump is actuated, pressurised air from the second pump chamber enters the mixing chamber through the second fluid passage means before liquid from the first pump chamber enters the mixing chamber through the first fluid passage means.

The dispenser may be configured such that, during use when the pump is actuated, air from the second pump chamber continues to enter the mixing chamber for a short period of time after the liquid from the first pump chamber has stopped flowing into the mixing chamber.

The dispenser may comprise a third fluid passage means for connecting the second chamber to the first fluid passage means at a position upstream from the mixing chamber.

The mixing chamber may be positioned immediately upstream of an outlet nozzle arrangement.

In accordance with a tenth aspect of the invention, there is provided a pump-action fluid dispenser comprising a manually actuated pump having a first pump chamber defined in part by a first flexible member which can be distorted from an initial configuration to a second configuration in order to reduce the volume of the first chamber and evacuate a fluid from the first chamber and a second pump chamber laterally spaced from the first, the second pump chamber being defined in part by a second flexible member which can be distorted from an initial configuration to a second configuration in order to reduce the volume of the second chamber and evacuate a fluid from the second chamber, characterised in that the dispenser further comprises an actuator member configured to engage and distort the first and second flexible members when a force is applied by a user to actuate the pump means; characterised in that the actuator member is configured to rock, tilt, deform or distort in order to fully evacuate both chambers.

The actuator may have a first, free end and a second end which is mounted to a support by means of a flexible hinge for pivotable movement of the member about the hinge, the actuator member being configured to rock, tilt, deform or distort at a position between the two ends in order to fully evacuate both chambers.

The actuator member may have two abutment means configured so that when a force is applied by a user, a first one of the abutment means contacts and distorts the first flexible member and a second one of the abutment means contacts and distorts the second flexible member.

The dispenser may be configured so that, in use when a user applies a force to the actuator member to actuate the pump means, the second abutment means contacts and distorts the second flexible member before first abutment means contacts and distorts the first flexible member.

The dispenser may be configured so that, in use when a user applies a force to the actuator member to actuate the pump means, the first pump chamber is fully evacuated before the second pump chamber.

The first abutment may be positioned between the second abutment and the hinge and the actuator member may be configured to rock, tilt, deform or distort about the first abutment member.

In accordance with an eleventh embodiment of the invention, there is provided a pump-action dispenser comprising a pump unit having an outlet nozzle, a fluid storage chamber and a manually actuated pump means for delivering a fluid from the fluid storage chamber to the outlet nozzle, characterised in that the dispenser further comprises a separate casing which at least partially encases the pump unit.

The casing may completely encase the pump unit.

The casing may be separable from the pump unit, so that the pump unit can be replaced by a similar pump unit.

The casing may include an actuator member to which a user can apply a force to actuate the pump.

The various aspects of the invention can be applied to any pump-action or trigger type dispenser for use with any type of fluid of any viscosity and which, where the fluid is a liquid, may be adapted to dispense the liquid in the form of a spray or a bolus or as a foam. The various aspects of the invention are applicable to dispensers having a wide range of discharges and which can be made to produce droplets of any suitable or desired size from under 5 microns up to 150 microns.

Several embodiments of a dispenser in accordance with the various aspects of the invention will now be described, by way of example only, with reference to the accompanying drawings in which:

FIG. 1 is a perspective view taken from one side and below of a dispenser in accordance with a first embodiment of the invention;

FIG. 2 is a perspective view taken from one side and above of the dispenser of FIG. 1 but with the lid removed;

FIG. 3 is a perspective view taken from below and to one side of a lid forming part of the outer casing of the dispenser of FIG. 1;

FIG. 4 is a perspective view from one side of an engine forming part of the dispenser of FIG. 1;

FIG. 5 is a further perspective view of the engine of FIG. 4 but taken from the other side;

FIG. 6 is a schematic sectional view through the engine of FIG. 4;

FIG. 7 is a scrap sectional view through part of the engine of FIG. 4 showing a fluid passage connecting a second pump chamber with a pre-compression valve;

FIG. 8 is a perspective view of a rigid frame forming part of a base member of the engine of FIG. 4;

FIG. 9 is a perspective view of a rigid frame forming part of a cover member of the engine of FIG. 4;

FIG. 10 is perspective view of an alternative casing for a dispenser in accordance with the invention;

FIG. 11 is an exploded, perspective view of the casing of FIG. 10 showing the casing being assembled to an engine;

FIG. 12 is an exploded, perspective view of a second embodiment of an engine for a dispenser in accordance with the invention;

FIG. 13 is a plan view of a base member forming part of the engine of FIG. 12;

FIG. 14 is a cross sectional view through the engine of FIG. 12 taken on line A-A of FIG. 13 but also showing details of the cover; and

FIG. 15 is a cross sectional view through the engine of FIG. 12 taken on line B-B of FIG. 13 but also showing details of the cover.

The same reference numerals will be used to denote the same or similar features in the various embodiments described where appropriate.

The invention will be described initially with reference to FIGS. 1 to 9 which show a dispenser 10 adapted for use in dispensing a nasal spray. It will be appreciated, however, that dispensers in accordance with the invention can be made in a variety of shapes and sizes suitable for a wide range of applications.

The dispenser 10 comprises an outer casing 12 and a pump unit or engine 14 received within the casing. The engine 14 has an integral storage chamber 16 for receiving a fluid to be dispensed, an outlet nozzle arrangement 18 and a manual pump mechanism 20, which when actuated draws fluid from the storage chamber 16 and dispenses it through the outlet nozzle arrangement 18. As described in more detail below, in the present embodiment the fluid in the storage chamber 16 is a liquid that is mixed with air in the outlet nozzle arrangement. However, it should be understood that a dispenser in accordance with the invention is not limited to this arrangement and can be adapted to dispense any fluid or combination of fluids as desired, including a liquor whether mixed with air or any other gas or not, two or more liquids or liquors, and any one or more gases. The storage chamber 16 comprises a fluid source for the dispenser 10.

The outer casing 12 has a main body member 22 that receives an upper portion of the engine 14. The main body portion 22 includes a top 22A with a nasal protrusion 22B adapted to be inserted into or close to a user's nostril. The protrusion 22B is hollow and is configured to receive the nozzle arrangement 18 of the engine 14 when the engine is positioned in the casing. An outlet opening 24 in the top of the protrusion 22B aligns with an outlet orifice 25 of the nozzle arrangement 18 so that fluid can be dispensed through the outlet opening 24 in the protrusion and into a user's nostril.

The main body member 22 also includes a skirt member 22C that extends around the front of the engine and across both sides. On one side, the skirt member 22C has an actuator member in the form of a trigger or lever portion 26 that is pivotally joined to the remainder of the skirt portion along one edge by means of a live hinge 28. As will be described in more detail later, the trigger 26 can be depressed inwardly by a user to actuate the dispenser. Another forms of actuator member to which a user can apply a force to actuate the dispenser can be used.

The outer casing 12 also includes a generally U shaped under body member 30 that is pivotably connected to the skirt member 22C along a front edge by a further live hinge 32. In certain embodiments, a filling opening 30A is provided in a lower portion of the under body member 30. Where provided, the filling opening 30A aligns with a corresponding filling opening of the integral storage chamber 16 of the engine 14. This enables the storage chamber 16 to be filled or re-filled with the engine 14 in-situ in the outer casing.

A lid 34 is connected to under body member 30 along a rear edge by a yet further live hinge 36. The lid is shaped so as to cover the top 22A of the main body member 22 when it is in a closed position as shown in FIG. 1. In order to use the dispenser, the lid 34 is pivoted away from the main body member 22 in the direction of arrow A in FIG. 1 about the hinge 36 in order to expose the nasal protrusion 22B. FIG. 3 shows the underside of the lid 34 which includes a number of strengthening ribs 38 and an annular member 37 that is configured to receive the nasal protrusion 22B when the lid is closed.

Also formed on the underside of the lid is a lock tab 40 that projects into a corresponding recess or opening 42 in the trigger 26 when the lid is closed. The lock tab 40 is designed to prevent the trigger 26 from being depressed when the lid is closed and so preventing the dispenser from being inadvertently actuated.

The outer casing 12 can be manufactured from any suitable material using any suitable methods. Although the lid 34 is shown separately in FIG. 3 and is omitted from FIG. 2 for clarity, in most embodiments it is expected that the lid 34 will be formed integrally with the under body member 30 and the main body member 22 as a one piece moulding from one or more plastics materials. The outer casing 12 may, for example, be manufactured from two or more different plastics materials using bi-injection moulding techniques. It should be appreciated, however, that the various components of the outer casing could be produced separately and assembled to form the outer casing.

The casing 12 can be produced in a variety of shapes, sizes and colours and may be over moulded with a material having a soft touch. A range of differently coloured and/or shaped and/or textured casings can be provided for use with the same engine 14.

When initially assembling the engine 14 into the casing 12, the casing is in an open condition in which the under body member 30 is pivoted away from the main body member 22 in the direction of arrow B in FIG. 1 about the live hinge 32 and the lid 34 is pivoted in the direction of arrow A relative to the under body portion 30 about the lid hinge 36. The engine 14 is inserted into the main body member 30 so that the nozzle portion 18 of the engine is received within the nasal protrusion 22B. With the engine 14 in position, the under body member 30 can be pivoted towards the main body member 22 (in the opposite direction to arrow B in FIG. 1) about the hinge 32 until the engine 14 is fully encased and the edges 44 of the under body member 30 abut with the corresponding edges 46 of the main body member 22 as shown in FIG. 1.

Suitable catch means are provided between the under body member 30 and the main body member 22 so that the two are held together in the closed position, preferably with a snap fitting. The lid 34 can then be closed by pivoting it about the lid hinge 36 in a direction opposite to that of arrow A in FIG. 1, until it reaches the closed position as shown in FIG. 1. Again, catch means may be provided between the lid 34 and the main body portion 22 to hold the lid in the closed position.

To use the dispenser, a user simply opens the lid 34, places the nasal protrusion 22B into or close to a nostril and depresses the trigger 26 to actuate the dispenser. After use, the lid 34 is closed to keep the top of the dispenser and the nasal protrusion 22B clean and to prevent the trigger from being inadvertently depressed.

The engine 14 will now be described with reference to FIGS. 4 to 9. Of these, FIGS. 6 and 7 are schematic cross sectional drawings of the engine 14 designed to show the functional relationship between the various parts. Certain of the constructional details shown in these two drawings are not consistent with the corresponding details in the remaining drawings but those skilled in the art will readily appreciate the differences and will have no difficulty in understanding how the engine is constructed and how it operates.

The engine 14 comprises a base member 48 and a cover member 50 that together define the integral storage chamber 16, the outlet nozzle arrangement 18 and the pump mechanism 20.

The base and cover members 48, 50 each comprise a rigid frame 49, 51 to which are attached one or more flexible components. The base and cover members can be manufactured from any suitable materials using any suitable techniques but are conveniently manufactured from plastics materials using bi-injection moulding techniques that enable the soft, flexible components to be over moulded on to the rigid frame 49, 51. Most conveniently, the engine 14 is moulded as a single integral item with the base and cover members 48, 50 interconnected by means of flexible hinge means (not shown) for subsequent assembly.

The storage chamber 16 is defined between a concave, substantially rigid wall portion 52 of the cover 50 and a flexible wall portion 54 that, in the present embodiment, is over moulded onto the rigid framework 49 of the base member 48. As shown in FIG. 4, the flexible wall portion 54 is configured so that in its natural rest position it follows closely the contour of the rigid wall portion 52 so as to minimise any gap between them. In an alternative embodiment, the flexible wall could be over moulded directly on to the rigid wall portion 52 of the cover using means to ensure that the flexible material does not adhere or bond with the rigid wall portion except at its edges.

A filler opening 58 is provided at one end of the storage chamber 16 so as to align with the filling opening 30A in the outer casing. As shown in FIG. 4, the storage chamber filler opening can be formed by means of opposing, rigid, curved formations 60, 62 on the base and cover members 48, 50 respectively. The curved formations 60, 62 being configured so as to define a circular opening into the chamber when the base and cover members are joined together. As shown in FIG. 4, the flexible wall portion 54 is over moulded onto the rigid, curved formation 60 of the base member so that a filler nozzle inserted into the filler opening 58 can direct a liquid, or other fluid, into the storage chamber 16 between the flexible wall portion 54 and the rigid wall portion 52. Once filling has been completed, the filler opening 58 can be closed by means of a bung or the like. The bung may be designed so that it cannot be removed or it may be removable to allow re-filling. Where the bung is removable, it may be conveniently attached to the outer casing 12 by a flexible hinge means. This later arrangement has the further advantage of reducing costs as there are fewer components if a hinged bung is used.

In an alternative embodiment (not shown), instead of the base member 48 having a rigid, curved formation 60, the flexible wall portion 54 can be extended to overlay the rigid, curved formation 62 on the cover. In this arrangement, the flexible wall member 54 will normally be configured to conform to the shape of the rigid, curved formation 62 to seal the filler opening. In order to fill the chamber, a filler nozzle is inserted between the flexible wall portion 54 and the rigid, curved formation 62 to enable the liquid to be injected into the storage chamber 16. When the filler nozzle is removed, the flexible portion will snap back into contact with the rigid, curved formation to seal the filler opening. A bung, clip or other closure device (not shown) can then be inserted to seal the flexible wall portion 54 tightly against the rigid, curved formation 62. An advantage of this embodiment is that the flexible wall portion will help to form a seal about the filling nozzle. In a further modification, the rigid, curved formation 62 on the cover member could also be replaced by a lip of flexible material (not shown) which can be over moulded onto the cover member 50 to ensure an even better seal.

The pump 20 comprises two pump chambers, a first pump chamber 64 for pumping the liquid from the storage chamber 16 and a second pump chamber 66 for pumping air to mix with the liquid in the outlet nozzle arrangement 18.

The first pump chamber 64 is defined between a rigid concave wall portion 68 of the base member 48, and a flexible dome or diaphragm 70 over moulded onto the inner end of a cylindrical wall formation 72 of the cover member 50. The first chamber 64 is in fluid connection with the storage chamber 16 by means of a passage 74 formed by means of corresponding groove formations in the base member 48 and the cover member 50. A flexible flap member 76 acts as a one-way valve to control movement of the liquid from the passage 74 into the first pump chamber 64. As shown, the flap valve 76 can be formed as an integral extension of the flexible dome 70. However, this is not essential and the flap 76 may be provided separately from the dome 70. Indeed, any suitable one-way valve mechanism can be used as appropriate. The first pump chamber 64 is also in fluid connection with a first expansion chamber 76 forming part of the outlet nozzle arrangement 18 by means of a further fluid passage 78 and a pre-compression valve 80.

The second pump chamber 66 is defined within the cylindrical wall portion 72 of the cover member 50 between an outer surface of the flexible dome 70 and a plunger or piston 82. The plunger 82 is formed from a rigid plastics material and is movably mounted to the cover member 50 by means of an annular rolling diaphragm 84. The rolling diaphragm 84 has a rigid collar portion 86 that is firmly mounted to an outer surface of the cover member 50 about the outside of the cylindrical wall portion 72 by any suitable means. In this regard, the collar portion 86 may be pushed onto another collar (not shown) formed as part of, or which is fixed to, the cover member 50 so that they lock together by friction. The rolling diaphragm also has a resiliently flexible portion 88 that extends from the collar portion 86 up and over the cylindrical wall portion 72, with the plunger 82 mounted to the inner end of the flexible portion 88 inside the cylindrical wall portion 72. The arrangement is such that the plunger 82 can be depressed into the second pump chamber 66 in the direction of arrow C in FIG. 6, which movement is accommodated by the rolling diaphragm 84. When the force depressing the plunger 82 is removed, the resilience of the flexible portion 88 of the rolling diaphragm draws the plunger back out of the second chamber 66 to a rest position as shown in FIG. 6. The plunger 82 includes an extension 90 that projects away from the second chamber 66 and which is contacted by the trigger 26 forming part of the outer casing to move the plunger 82 when the trigger is depressed by a user to actuate the pump. A flexible lip 92 on the inner end of the rolling diaphragm 84 is arranged to contact the inner surface of the cylindrical wall portion 72 of the cover member to form a seal. An array of holes 94 in the flexible portion 88 of the rolling diaphragm 84 allows ambient air to be drawn into the second pump chamber past the lip seal 92 as the plunger returns to the rest position shown in FIG. 6.

The plunger 82 and rolling diaphragm 84 can be made of any suitable materials using any suitable manufacturing techniques but conveniently is manufactured as an integral component from plastics materials using bi-injection moulding techniques. Thus the plunger 82 and the collar portion 86 of the rolling diaphragm 84 can be moulded from a first relatively rigid plastics material and the resiliently flexible portion 88 can be over moulded onto the plunger and collar using a second, resiliently flexible material. Most conveniently, the plunger and rolling diaphragm are produced integrally with the cover member 50 as a single moulding. As shown in FIG. 5, the rigid collar 86 of the rolling diaphragm 84 may be connected to the rigid framework of the cover member 50 by means of a flexible hinge means 92 to enable them to be moulded as a single integral component for later assembly. Alternatively, the rolling diaphragm 84 and plunger 82 may be formed integrally with the base member 48.

Whilst it is advantageous for the rolling diaphragm 84 and/or the plunger 82 to be formed integrally with one of the cover member 50 or the base member 48, it will be appreciated that they could be produced as separate components either from each other or from the cover member 50 or base member 48.

The second pump chamber 66 is fluidly connected to the first expansion chamber 76 of the nozzle arrangement 18 by means of a further fluid passage or channel 96 and the pre-compression valve 80 as shown in FIG. 7.

The pre-compression valve 80 is of the peg and recess type described in International patent application WO 2005/068084 A1, to which the reader is referred for a full description of the valve's construction and operation. However, briefly, the valve 80 comprises a round headed circular peg 98 formed of a substantially rigid material as part of the base member 48. The peg 98 is received in a correspondingly shaped recess 100 formed in the cover member 50. Two grooves 102, 104 are provided in the surface of the peg. As shown in FIG. 8, a first groove 102 forms a continuation of the fluid passage 78 connecting the first pump chamber 64 with the valve 80. The first groove 102 extends from the passage 78 up the upstream side of the peg, around an upper portion of the peg and part way down the downstream side of the peg adjacent the first expansion chamber 76. Similarly, the second groove 104 forms a continuation of the fluid passage 96 connecting the second pump chamber 66 with the valve 80 and extends from the passage 96 up the upstream side of the peg, around an upper portion of the peg, on the opposite side of the peg from the first groove 102, and part way down the downstream side of the peg adjacent the first expansion chamber 76.

A dome of resilient, flexible material 106 is over moulded into the recess 100 in the cover member and is a close sealing fit on the top of the peg 98 when the cover member 50 and base ember 48 are joined together. On the downstream side, the flexible dome 106 extends beyond the end of the two grooves 102, 104 to form a collar 108 which seals against the surface of the peg 98 closing off the grooves from the first expansion chamber 76.

The collar 108 acts as a valve to control the release of the fluid in the grooves 102, 104 into the first expansion chamber 76 and is configured such that it engages the peg to seal the grooves 102, 104 and prevent the fluid entering the first expansion chamber 76 so long as the fluid in the grooves is below a predetermined pressure. Once the pump is actuated and the fluid in the grooves 102, 104 reaches the predetermined pressure, the collar 108 is designed to move away from the peg 98, preferably with a snap action, opening the grooves 102, 104 to permit the fluid to enter the first expansion chamber 76. If the pressure of the fluid in the grooves 102, 104 drops below the predetermined pressure, the collar 108 is designed to snap back into engagement with peg to seal the grooves 102, 104.

By appropriate design, the valve 80 can be set to open only once the fluid in the pump chambers 64, 66, fluid passageways 78, 96 and corresponding grooves 102, 104 reaches a desired pressure required so that the fluid forms a suitable aerosol or atomised spray as it passes through the nozzle arrangement 18. Typically, the pre-compression valve 80 will be set to open at a pressure in the range of 0 to 20 bars and more typically in the range of 2 to 8 bars.

Normally the collar 108 will open both grooves 102, 104 simultaneously at the same pressure but it can be configured to open the grooves at different pressures. The pre-compression valve 80 also operates as a one way valve preventing fluid being drawn back into the pump chambers thorough the grooves 102, 104. This is particularly advantageous as it prevents any liquid that might be present in the nozzle from being drawn in into the air chamber 66 when the pump is released by a user.

The pre-compression valve 80 can be modified in accordance with the teachings of WO 2005/068084 A1 GB, the content of which is hereby incorporated by reference in its entirety. For example, separate pre-compression valves may be used to control the air and the liquid. Furthermore, the invention is not limited to use of peg and recess type valves and any suitable type of valve or valves can be used.

The nozzle arrangement 18 essentially comprises a fluid outlet passage that connects the pre-compression valve 80 with the final outlet orifice 25. The nozzle arrangement 18 can take many different forms according to the needs of the particular application. The nozzle arrangement may, for example, include any of the flow control means disclosed in the applicant's International patent application published as WO 01/89958 A1, the content of which is incorporated in its entirety. As shown in FIGS. 6 and 7, the nozzle arrangement may include a first expansion chamber 76 into which the liquid and the air are directed from the grooves 102, 104 respectively. The first expansion chamber is followed by an internal orifice 112 that comprises a narrow hole leading into a second expansion chamber 114. The arrangement is such that the fluid passing through the inner orifice is sprayed into the second expansion chamber 114. The second expansion chamber is provided adjacent the final outlet orifice 25.

Conveniently, the chambers 76, 114 and the inner and final orifices are circular in cross section and are formed by means of corresponding grooves or recesses in the base and cover members. However, the chambers 76, 114, inner orifice and other fluid passage portions can be of any shape and in particular may be any of the shapes disclosed in International patent application published as WO 2005/005055 A1 or International patent application No. GB2005/004415, the entire contents of which are hereby incorporated by reference. Thus, it should be understood that the shape of any of the fluid flow passage portions or chambers in any of the embodiments described herein can be modified in accordance with the principles discussed in WO 2005/005055 A1 or GB2005/004415.

FIGS. 8 and 9 illustrate an alternative nozzle arrangement 18′ in which the first expansion chamber 76 is connected to a swirl chamber 116 formed adjacent the outlet orifice 25 by means of a fluid passage 118 that directs the fluid into the swirl chamber tangentially.

In the disclosed nozzle embodiments 18, 18′, the liquid and the air exiting the grooves 102, 104 of the pre-compression valve mix in the first expansion chamber 76. The grooves 102, 104 can be configured to direct the air and the liquid into the chamber in any desired manner to ensure effective mixing. For example, the grooves 102, 104 may be configured to direct the fluids into the chamber tangentially or non-tangentially, they may direct the liquid and air in streams that collide with one another or they may direct the streams away from one another and which may be directed towards the walls of the chamber, for example.

It will be appreciated that many different nozzle formations can be adopted. For example, whilst in the present embodiment the outlet orifice 25 is directed upwardly for effective use as a nasal spray, the outlet orifice could be arranged to discharge the fluid at right angles to the direction shown. Furthermore, the nozzle outlet arrangement could include more than one fluid flow passage and more than one outlet orifice and the two fluids could be mixed at a point downstream of the first expansion chamber or even mixed only once the fluids have exited the nozzle through separate fluid flow passages and outlet orifices.

For applications other than a nasal spray, there will be no need for a nasal projection 22B. This means that the outlet nozzle arrangement 18 can be formed much closer to the pump chambers 64, 66 and may even be arranged to come out directly underneath them. In this case, it may be possible to dispense with the pre-compression valve 80 altogether, or to incorporate a degree of pre-compression into the outlet valve(s) of the pump chamber(s). Alternatively, auxiliary pre-compression valves may be used.

Operation of the dispenser will now be described. For the purposes of this description it will be assumed that the storage chamber 16 is full of the liquid product and that both of the pump chambers 64, 66 are fully charged.

To actuate the dispenser, the user opens the lid 34 and positions the outlet 24 as required. The user then depresses the trigger 26 which contacts the extension 90 of the plunger 82 causing the plunger to move towards the flexible dome 70 in the direction of arrow C in FIG. 6. At this stage, the collar 108 of the pre-compression valve 80 is in contact with the peg 98 sealing off the grooves 102, 104 so that the fluid in the grooves is unable to enter the first expansion chamber 76 of the nozzle 18. As a result, the movement of the plunger 82 causes the pressure of the air in the second pump chamber 66, the fluid passage 96 and groove 104 to rise. The increased pressure of the air in the second pump chamber 66 forces the lip seal 92 into closer engagement with the cylindrical wall portion 72 to ensure an adequate seal is formed. The increased pressure of the air in the second pump chamber is also transmitted via the flexible dome 70 to the liquid in the first pump chamber 64 so that the pressure of the fluid in the first pump chamber 64, the fluid passage 78 and the groove 102 increases proportionally with that of the air in the second pump chamber 66. In a preferred embodiment, the arrangement is such that the pressure of the liquid in the first pump chamber 64 remains substantially equal to the pressure of the air in the second pump chamber 66. Because the pre-compression valve 80 is closed and the liquid is incompressible, the flexible dome 70 will not be depressed at this stage.

Further movement of the plunger in the direction of arrow C causes the pressure of the liquid and the air in the pump chambers 64, 66, fluid passageways 78, 96 and grooves 102, 104 to increase until it reaches a predetermined value at which the collar 108 of the pre-compression valve is moved away from the peg 98. As the collar 108 moves away from the peg 98, the grooves 102, 104 are opened allowing the liquid and the air to enter the first expansion chamber 76 and to pass through the nozzle arrangement 18 before exiting the outlet orifice 25 as a spray. Once the pre-compression valve has opened, further inward movement of the plunger 82 will continue to deliver air from the second pump chamber 66 into the nozzle arrangement and will cause the flexible dome 70 to be depressed to also deliver liquid under pressure into the nozzle arrangement 18. During this phase, the inlet flap valve 76 remains closed preventing the fluid in the first pump chamber 64 from passing back into the storage chamber 16. This phase continues until all the liquid in the first pump chamber 64 has been expelled and the flexible dome 70 is in contact with the concave wall portion 68 of the base member.

The pump may be configured so that air continues to be delivered through the nozzle after the liquid has been fully ejected to clean out any liquor remaining the nozzle 18 or it may be configured so that both the liquor and air are fully ejected at the same time. The pump may also be configured to allow air to be pumped through the nozzle 18 before the liquid is ejected. The rate of flow of the air and/or the liquid can be controlled, for example, by creating a set sized hole anywhere between the outlet from the respective pump chamber 64, 66 and the respective groove 102, 104 around the pre-compression valve peg 98.

Once the plunger has been fully depressed and the fluid and air ejected from the first and second pump chambers 64, 66, the pressure of the fluid in the grooves 102, 104 will drop below the predetermined level and the collar 108 of the pre-compression valve 80 will close to again seal the grooves 102, 104. The user will then release the trigger 26 allowing the rolling diaphragm 84 to draw the plunger 82 back out of the cylindrical wall portion 72. Because the pre-compression valve is closed, this will cause a partial vacuum to be formed in the second pump chamber 66. The lip seal 92 is configured such that it is resiliently biased against the cylindrical wall portion 72 and so does not initially allow air to enter the second pump chamber 66 through the air inlet holes 94. As a result, the partial vacuum in the second pump chamber 66 acts to draw the flexible dome 70 away from the concave portion 68 of the base member 48. This in turn creates a partial vacuum in the first pump chamber 64 and so draws liquid into the first pump chamber 64 from the storage chamber 16 via the inlet flap valve 76 which is lifted away from its seat. The lip seal 92 is configured so that it does not open to admit air into the second chamber 66 until the first pump chamber 64 is fully charged. Once the first pump chamber 64 is fully charged, the lip valve 92 opens so that air is drawn into the second pump chamber 66 until the plunger 82 has returned to the rest position as shown in FIG. 6 and both pump chambers are fully charged ready for further actuation. Movement of the plunger 82 to the rest position is transmitted via the extension 90 to the trigger 26 so that the trigger 26 is also moved to the rest position.

In many applications it is expected that the flexible dome 70 separating the first and second pump chambers 64, 66 will not have any strong resilience or elasticity or would at least be less resilient than the collar 108 of the pre-compression valve 80. However, in certain applications it may be desirable to have the pressure of the air higher than that of the liquor during actuation of the dispenser and this can be achieved by use of a dome 70 of increased resilience. In a modification (not shown) the plunger may be provided with an actuation member that contacts the flexible dome 70 to physically depress the dome 70 when the pump is actuated.

An advantage of the present embodiment is the use of a flexible wall portion 54 in the storage chamber 16 which minimises the amount of air in the storage chamber 16. Any residual air that is present in the chamber 16 after filling will tend to accumulate at the top of the chamber, when the dispenser is held upright for use, and can be exhausted when the pump 20 is primed ready for use. This could be done as part of the process for filling the dispenser to ensure that there is no, or only minimal, air present in the chamber 16 when the device is made available to an end user. Alternatively, it can be arranged for any residual air in the chamber 16 to be sucked out by the filling nozzle before filling commences. A result of this is that only the liquid product is drawn into the pump chamber. This provides a more consistent dosing of the product than provided by conventional pump action dispensers that use a dip tube and in which a mixture of air and liquid product can be drawn into the pump chamber. Furthermore, each time a volume of liquid is drawn from the fluid storage chamber, the flexible wall portion will tend to move closer to the rigid wall portion so reducing the volume of the chamber by an equivalent amount. This eliminates the need to a pressure relief valve to admit air into the fluid storage chamber. A further advantage of this arrangement is that the dispenser can be repeatedly actuated in any orientation. The arrangement also means that the conventional dip tube can be dispensed with.

The flexible wall portion 54 may be resiliently biased towards the rigid wall 52 so that it pressurises the fluid in the storage chamber 16. This can assist in refilling the first pump chamber 64. Alternatively, the flexible wall 54 could have virtually no elasticity and rely on external air pressure to press it towards the rigid wall 52 as the liquid is drawn from the storage chamber.

The formation of a fluid storage chamber comprising a flexible wall as described above can be used with any type of pump-action fluid dispenser. It is also possible to construct a separate fluid container for mounting to a pump-action dispenser using the same principles.

In a further alternative embodiment (not shown), the flexible wall 54 may be produced as a mirror image of the rigid wall so that a more conventional storage chamber is provided. In a yet further alternative, the storage chamber could be provided with both walls 52, 54 made of a flexible material or by means of a bladder or bellows arrangement. Furthermore, the storage chamber could be provided with rigid walls on both sides and an air release valve to enable air to enter the chamber as fluid is drawn into the first pump chamber. A dip tube may be required with this arrangement. Alternatively, the integral storage chamber can be replaced by a separate bottle or container to which the remainder of the engine 14 is mounted in a manner similar to a conventional pump action dispenser

FIGS. 8 and 9 show the rigid frame portions 49, 51 of the base member 48 and the cover member 50 respectively. The frame portions 49, 51 have corresponding faces 120, 122 that are designed to mate when the base member 48 and the cover member 50 are joined together. Many of the components of the engine 14, such as the nozzle arrangement 18 and various of the fluid flow passageways, are formed by means of corresponding grooves and/or recesses or other formations in the faces 120, 122 of the rigid frame portions when the base and cover members are assembled. A seal means is provided between the base and cover members 48, 50 to prevent leakage. The seal means is formed by means of one or more ridges 124 that protruded from the surface 120, 122 of one of the base and cover members 48, 50 and which is/are received in a corresponding one or more grooves or slots 126 in the surface 120, 122 of the other of the base and members 48, 50. As can be seen from FIGS. 8 and 9, seal means extend around most of the components of the engine, including the storage chamber 16, the pump 20 and the nozzle arrangement 18. The seal means may be continuous or discontinuous as necessary to enable fluid communication between the various features of the engine.

When the base and cover members 48, 50 are assembled, they may be joined together by any suitable means such as by bonding or welding. Alternatively, at least the join between the base and cover members 58, 50 may be over moulded.

A curved rigid shield 128 projects from the cover member 50 and extends part way around the rolling diaphragm 84. The shield helps to support the outer casing 12 to enable free movement of the trigger 26.

The design of the first embodiment of the engine 14 may be varied in numerous ways. Thus the rolling diaphragm 84 could be replaced by means of a flexible dome or equivalent with an air return valve or using a conventional plunger or piston with a return spring. Furthermore, the flexible dome 70 defining the first pump chamber 64 could be replaced by another plunger or piston. In a further alternative embodiment (not shown) the design of the rolling diaphragm 84 in the first embodiment may be varied to omit the lip 92. This has the advantage of reducing friction between the rolling diaphragm 84, the plunger 82 and the cylindrical wall 72. In this arrangement, the holes 94 in the rolling diaphragm 84 would also be omitted to ensure that the air in the second chamber 66 is compressed when the plunder 82 is depressed. A separate air inlet passage controlled by an inlet valve would be provided to admit air into the second pump chamber 66 when the plunger 82 is drawn back out of the cylinder 72 to the rest position shown in FIG. 6. The inlet valve may be arranged so that it only admits air into the second pump chamber 66 once the vacuum in the second chamber has drawn the flexible dome 70 upwardly to recharge the first pump chamber 64. Alternatively, the flexible dome 70 may be resilient so that it acts to recharge the first pump chamber 64 without the assistance of a vacuum in the second pump chamber 66, in which case the inlet valve may admit air to the second pump chamber 66 once the pressure in the second pump chamber falls below atmospheric. The inlet valve may be of any suitable type and may, for example, be a flap type valve similar to the valve 76.

A second embodiment of a case for a dispenser 10 in accordance with the invention will now be described with reference to FIGS. 10 and 11.

The casing 12 comprises four main components: a first main body portion 121, a second main body portion 123 an over cap 125, and a nasal protrusion 127.

The first main body portion 121 forms a half shell having a cavity into which the engine 14 can be mounted and securely located by means of a resilient clip member 128. The clip 128 engages with a side portion of the engine and with one or more pin members 130 projecting from an inner surface of the main body portion. The first main body portion has an end wall 132 with a semi-circular opening 134 in which the nozzle 18 of the engine 14 locates.

The nasal protrusion 127 is attached to the first main body portion 121 by means of a flexible hinge 136 and is positioned over the nozzle 18, once the engine has been located in the first main body portion.

The second main body portion 123 forms a second half shell which clips to the first main body portion 121 to encase the engine 14. The first main body portion 121 and the outer surface of the engine 14 have a plurality of projections 138 which engage in corresponding holes formed in the second main body portion 123 to hold the first and second main body portions together. The second main body portion 123 has an end wall 140 with a semi-circular opening or recess 142 which engages with the nasal protrusion 127 to hold it in position. When assembled, the end walls 132, 140 of the first and second main body portions 121, 123 combine to form and end of the casing which is uppermost in use.

The over cap 125 is pivotally mounted to the first and second main body portions 121, 123 for movement between an open position in which the nasal protrusion and outlet are exposed, as shown in FIG. 10, and a closed position in which cap engages with the upper end of the casing to enclose the nasal protrusion. The over cap has an arm 144 which a pair of pivot pins 146 which engage in corresponding holes 148 in the first and second main body portions 121, 123 to enable the cover to move pivotally between the open and closed positions. The end wall 140 of the second main body portion 123 is shaped to accommodate the arm 144 for its movement between the open and closed positions.

To assemble the casing 12 and engine 14, the engine is located in the first main body portion 121 and secured in position. The nasal projection 127 is then positioned over the nozzle 18 following which the over cap 124 is assembled to the first main body portion 121. Finally, the second main body portion 123 is clipped to first main body portion 121 and the engine 14 to hold the assembly together.

The second main body portion 123 has an actuator lever or trigger portion 26 formed in a side wall portion. The trigger portion 26 is attached to the remainder of the second main body portion 123 by means of a live hinge 28 so that it can be depressed inwardly to actuate the engine pump mechanism as previously described.

As with the first embodiment, the outer casing 12 can be manufactured from any suitable material using any suitable methods but will typically be moulded from plastics materials. The casing 12 can be produced in a variety of shapes, sizes and colours and may be over moulded with a material having a soft touch. A range of differently coloured and/or shaped and/or textured casings can be provided for use with the same basic engine 14.

A further embodiment of a pump engine 14 for a dispenser in accordance with the invention will now be described with reference to FIGS. 12 to 15. The further pump engine can be used with either of the previously described cases subject to some minor modifications.

The engine 14 has an integral storage chamber 16 for receiving a fluid to be dispensed, an outlet nozzle arrangement 18 and a manual pump mechanism 20, which when actuated draws fluid from the storage chamber 16 and dispenses it through the outlet nozzle arrangement 18. As described in more detail below, in the present embodiment the fluid in the storage chamber 16 is a liquid or liquor that is mixed with air in the outlet nozzle arrangement. However, it should be understood that a dispenser in accordance with the invention is not limited to this arrangement and can be adapted to dispense any fluid or combination of fluids as desired, including a liquor whether mixed with air or any other gas or not, two or more liquids, and any one or more gases. The storage chamber 16 comprises a fluid source for the dispenser 10.

The engine 14 comprises a base member 48 and a cover member 50. In this embodiment, the base member is formed entirely from a substantially rigid material. The base member can be manufactured from any suitable material but will typically be formed from a plastics material, for example by injection moulding. The cover member is comprises a frame 51 to which is mounted, or formed integrally therewith, all of the flexible components of the engine 14. The cover member may be formed from any suitable materials but typically will be formed from two or more plastics materials using bi-injection moulding techniques. Thus the rigid frame 51 can be formed from a first plastics material in a first shot of the moulding process. The flexible components are then over moulded onto the frame in a second shot of the process. If necessary, the various flexible components can be formed from different flexible materials if different properties are required. The arrangement in which all the flexible components are formed on one of the pump members has the advantage that only one of the members need be formed as a bi-injected component, thus reducing manufacturing costs.

The liquid storage chamber 16 in this embodiment is similar to that of the previous embodiment and enjoys similar advantages. Thus the chamber 16 is defined between a concave recess or wall member 52 in an inner face of the base 48 and a flexible wall portion 54 on the cover 50. As can be seen best in FIG. 15, the flexible wall portion 54 is configured to conform closely to the contours of the concave recess 52 in its natural rest position so as to minimise the air space in the chamber. The flexible wall portion 54 may be made of a resilient material which is biased into contact with the rigid wall portion 52. Although not shown in the drawings, the liquid storage chamber 16 may have a filler opening through which a liquid to be dispensed can be introduced into the chamber in a manner similar to that of the first embodiment. The filler opening may be closed by means of a bung (not shown) which may be connected to the engine 14 or the case 12 by means of a hinge or which may be a separate component.

The pump 20 in the second embodiment differs from the pump in the first embodiment in that the two pump chambers 64, 66 are separate. Thus a first pump chamber 64 for receiving liquid from the liquid storage chamber 16 is defined between a rigid concave wall portion 68 of the base member 48 and a flexible dome or diaphragm 70 over moulded to the frame 51 of the cover member 50. A bore 150 in the base member 50 fluidly interconnects the liquid storage chamber 16 and the first pump chamber 64 to provide an inlet through which liquid can be drawn from the storage chamber 16 into the pump chamber.

Movement of the liquid into the first pump chamber is controlled by an inlet valve. The inlet valve comprises a resilient main flap 152 which overlies the opening of the bore 150 in the rigid wall portion 68. The main flap 152 is formed as an integral extension of the resilient dome 70 and is received in a recess 154 in the rigid wall portion 68 about the bore opening, which provides a valve seat. The main flap 152 is resiliently biased into contact with the wall 68 to close of the bore 150. The main flap 152 moves away from the rigid wall 68 when the pressure in the first pump chamber falls to a predetermined minimum value below the pressure of the liquid in the storage chamber 16, to allow liquid to be drawn into the first pump chamber. An auxiliary flap 154, also formed integrally with the dome 70 engages with the outer face of the main flap 152 to hold the main flap in contact with the rigid wall, especially when the dome is depressed to actuate the pump. This ensures that the main flap 152 forms an effective seal to enable the liquid in the first pump chamber to be pressurised.

The first pump chamber is fluidly connected with a mixing chamber 76 forming part of the outlet nozzle arrangement 18 by means of a further bore 156 in the base member 48, a liquid pre-compression outlet valve 80, and a fluid channel 158 in the base member 48.

The liquid outlet bore 156 has a first angled portion 156 a that leads into a second vertical portion 156 b. The vertical portion 156 b of the liquid outlet bore opens at the inner face of the base member where it is surrounded by an annular recess 158. The annular recess 158 forms a chamber of the liquid pre-compression valve 80 and is in fluid connection with mixing chamber 76 by means of the fluid channel 160 in the inner face of the base member. A lip 162 surrounds the opening of the bore 156 b into the pre-compression chamber to provide a valve seat for engagement by a resiliently flexible diaphragm 164 on the frame 51 of the cover member. The flexible diaphragm 164 acts as a valve member and is configured so that it is biased to engage the lip 162, closing off the opening of the bore 156 b and so preventing the liquid from entering the pre-compression chamber 158 and the outlet nozzle 18. However, the diaphragm 164 can be lifted away from the tip 162 by the liquid in the bore 156 b when the pressure of the liquid reaches a predetermined minimum value.

The second, air pump chamber 66 is defined between a further concave recess or rigid wall portion 166 formed in the inner face of the base member and a rolling diaphragm 168 mounted to the rigid frame 51 of the cover member. The rolling diaphragm is formed of a resiliently flexible material and is similar to the dome member 70 of the first pump chamber 64 but has a steeper side wall portion 168 a. An outer end (as shown) region 168 b of the rolling diaphragm has an inverted dome portion 168 c to give the outer end region a degree of rigidity. The arrangement is such that the outer end region 168 b can be depressed inwardly toward the rigid wall 166 to reduce the volume of the second pump chamber. The inward movement of the outer end region 168 b is accommodated by the side wall region 168 a which rolls inwardly and downwardly. When the inward pressure on the outer end region 168 b is removed, the resilience of the side wall region 168 a moves the outer end region 168 b away from the rigid wall 166 to restore the rolling diaphragm to its initially resiliently biased position as shown in FIG. 14.

An air inlet bore 170 is formed through the rigid wall portion 166 of the base 48 to admit ambient air into the second pump chamber. The admission of air into the second pump chamber is controlled by an inlet valve, similar to the inlet valve of the first pump chamber. Thus the air inlet valve comprises a main flap 172 which is received in a recess 174 in the rigid wall portion 166 about the opening of the bore to prevent air in the chamber from exiting through the bore when the rolling diaphragm 168 is depressed. The main flap 172 is normally biased to close the air inlet bore 170 but can be moved away from the surface of the recess 174 to admit air into the chamber when the pressure in the chamber is lower than the ambient air pressure by a predetermined minimum amount. The main flap 172 is formed integrally with the rolling diaphragm 168. An auxiliary flap 176, also formed integrally with the rolling diaphragm 168, is arranged to contact an outer face of the main flap 172 to press the main flap into contact with the surface of the recess 174 in the rigid wall portion 166 at least when the rolling diaphragm 168 is being depressed. This ensures that main flap 172 forms an effective seal so that the air in the chamber 66 can be pressurised.

The second pump chamber 66 has an outlet bore 178 in the base member 48 which leads to an air pre-compression valve 180. The air pre-compression valve 180 includes a pre-compression bore 182 which opens into a shallow concave recess 184 in the inner face of the base member 48 which forms an air pre-compression valve chamber. The air pre-compression valve chamber 184 is fluidly connected with the mixing chamber 76 by a groove or channel 186 in the inner face of the base member. The air pre-compression valve chamber 184 is also fluidly connected with the liquid pre-compression valve chamber 158 by a further groove or channel 188 in the inner face of the base member. A plunger 190 is formed integrally with a flexibly resilient diaphragm 192 mounted to the rigid frame 51 of the cover member. The plunger 190 is received in the pre-compression valve bore 182 when the cover 50 is mounted to the base 48 as shown in FIG. 14. The plunger has a seal means 194 that engages with the surface of the bore 182 to prevent air from the second pump chamber 66 entering the air pre-compression chamber 184 and the channels 186, 188. The diaphragm 192 is configured to resiliently bias the plunger 190 into the bore 182 to close the pre-compression valve 180. When the pump is actuated and the rolling diaphragm 168 depressed to pressurise the air in the pump chamber, the increased air pressure acts on the plunger 190 to move it out of the bore 182 to allow the air to enter the air pre-compression chamber 184 and the channels 186, 188. The valve is constructed so that the plunger will only be biased by the increased air pressure out of the bore 182 when the pressure of the air in the second pump chamber reaches a predetermined minimum value. When the pressure of the air acting on the plunger falls below the predetermined minim value, the resilient diaphragm 192 biases the plunger 190 back into the bore 182 to close the valve. The air pre-compression valve thus serves to ensure that the air only leaves the pump chamber when it is at the required pressure and acts as a one way valve to prevent liquid being drawn into the second pump chamber.

The mixing chamber 76 is formed by corresponding recess 76 a, 76 b in the base and cover members when the two are assembled. Further corresponding groves and recess in the inner faces of the base and cover members 48, 50 define an outlet orifice 25 of the nozzle 18, a swirl chamber 116 adjacent to and in fluid communication with the outlet orifice, and a fluid passage 118 that fluidly connects the mixing chamber and the swirl chamber 116 and which directs the mixed liquid and air into the swirl chamber tangentially to cause it spin in the swirl chamber.

A projection or ridge 124 is formed on the inner face 122 of the cover member 48 for engagement in a corresponding groove 126 in the inner face 120 of the base member to form a seal between the two members when they are assembled. The seal extends around and between the various chambers and the outlet nozzle 18, to prevent the liquid and air from seeping out between the base and cover members. Where the base and cover members are made of plastics materials, the two will generally be welded together using any suitable type of welding, including heat, laser and ultrasonic welding. Typically, the base and cover members will be welded together along the line of the seal so that the projection or ridge 124 melts into the corresponding groove 126. Additional recess may be formed in the base member into which the material melted during welding can flow so that this material does flow into and block the fluid flow passages and channels.

Operation of a dispenser comprising the further embodiment of the pump engine will now be described. This description assumes that the pump engine 14 is encased in a casing having a trigger 26, the storage chamber 16 is full of liquid and that the first and second pump chambers 64, 66 are both primed.

To actuate the pump engine 14 the user depresses the trigger 26 which compresses the rolling diaphragm 168 and the dome 70 to pressurise the liquid in the first pump chamber 64 and the air in the second pump chamber 66. Because there are two separate pump chambers, it is essential to ensure that the rolling diaphragm 168 and the dome 70 are depressed in the correct sequence. This is achieved by means of two prodders (not shown) on the inside of the trigger 26, each of which engages with a respective one of the rolling diaphragm 168 and the dome 70. The arrangement is such that a first prodder initially engages the rolling diaphragm 168 so that the rolling diaphragm is compressed, reducing the volume of the second pump chamber and pressurising the air inside. Once the air in the second pump chamber 66 has been pressurised to a predetermined value, which may be in the region of 3 bar, the second prodder engages the dome 70 to pressurise the liquid in the first chamber. At this stage, at least one of pre-compression valves 80, 180 will open to allow further compression of the rolling diaphragm 168 and the dome 70. Preferably the air pre-compression valve 180 opens initially so that pressurised air is able to pass through the air pre-compression chamber 184, with a portion of the air passing through the channel 186 to enter the mixing chamber 76 and a further portion of the air passing through the channel 188 to enter the liquid pre-compression chamber 158. Approximately one third of the air flows through the channel 188 into the liquid pre-compression chamber while the remaining two thirds flows into the mixing chamber. The proportions of the air flowing to the liquid pre-compression chamber and the mixing chamber can be varied as required.

The liquid pre-compression valve 80 may open at the same time as the air pre-compression valve 180 or very slightly later as a result of the pressurised liquid acting on the diaphragm 164. If the liquid pre-compression valve 80 opens after the air pre-compression valve 180, the pressurised air entering the liquid pre-compression chamber 158 may act on the diaphragm 164 to assist in opening the liquid pre-compression valve 180.

Once both pre-compression valves 80, 180 are open, continued depression of the trigger 26 causes the rolling diaphragm 168 and the dome 70 to be compressed further so that pressurised air continues to flow though the air pre-compression valve 180 and liquid continues to flow through the liquid pre-compression valve 80. The portion of the pressurised air that flows through the channel 188 into the liquid pre-compression chamber mixes with the liquid and helps to drive the liquid along the channel 157 into the mixing chamber 76 where it mixes with the majority of the air flowing into the mixing chamber 76 through the channel 182. The air and liquid streams entering the mixing chamber 76 are thoroughly mixed before flowing through the fluid passage 118 into the swirl chamber 116 and through the outlet as an atomised spray.

Ejection of the liquid through the outlet continues until the dome 70 is fully compressed. At this point, the pressure in the first chamber will fall and the liquid pre-compression valve 80 will close. The pump may be arranged so that both the rolling diaphragm 168 and the dome 70 become fully compressed at the same time but it is preferable if the rolling diaphragm 169 continues to be compressed for a short while after dome, so that pressurised air is delivered through the nozzle and the liquid pre-compression chamber 158 to clear out any remaining liquid from the flow passages. Once the air chamber 66 is fully compressed, the air pressure inside the chamber will fall and the air pre-compression valve 180 will close.

The actuator or trigger 26 is designed to rock, tilt, deform or distort slightly to continue depressing the rolling diaphragm 168 when the dome 70 is fully depressed. Thus the first abutment portion is arranged closest to the hinge 28 for contact with the dome 70 and the second abutment portion is arranged closet to the free end of the trigger for contact with the rolling diaphragm 168. Once the first chamber 64 is fully evacuated and the dome 70 is in contact with the rigid wall 68, further downward movement of the first abutment portion is prevented. In order for the second abutment portion to continue depressing the rolling diaphragm 168, the trigger 26 has to either rock, tilt, deform or distort about the first abutment portion. The amount of movement required is small (in the order of a few millimetres or less) and this movement may be accommodated by the flexibility of the trigger 26 itself, especially where it is made of plastic.

Once spraying has stopped, the user now releases the trigger 26 and the dome 70 and the rolling diaphragm 168 return to their initially resiliently biased configurations, as shown in FIGS. 14 and 15, due to the resilience of the material and their design. As the rolling diaphragm 168 and dome 70 recover to their initial configurations, the volume of each of the chambers 64, 66 increases and, because the outlet pre-compression valves 80, 180 are both closed, the pressure in the chambers falls. Once the pressure in each chamber 64, 66 falls below the respective predetermined minimum value, inlet valve flaps 152, 172 open to allow a fresh charge of liquid to be drawn into the first pump chamber 64 from the liquid storage chamber 16 and a fresh charge of air to enter the second pump chamber 66 through the air inlet bore 170. The dispenser is then ready for a further actuation. This process can be repeated until the substantially fluid in the storage chamber 16 has been used up.

Mixing of a portion of the air with the liquid in the mixing chamber 76 helps in the break up of the liquid into droplets and so improves the quality of spray and reduces the occurrence of jetting. To prevent jetting occurring at the beginning of the spray sequence, it is preferable for the pump to be constructed so that a stream of pressurised air enters the mixing chamber 76 before the stream of liquid. Similarly, to prevent jetting at the end of the spray sequence, it is preferable that the stream of air continues to flow into the mixing chamber 76 after the liquid has stopped flowing. The relative volumes of the first and second chambers can be adjusted. The volume of air may be 3 to 50 times greater than that of the liquid but in most applications the volume of air will be 10 to 30 times greater than the volume of liquid. The mixing chamber 76 in the present embodiment is cylindrical but it can be any shape, including part spherical, which encourages mixing of the air and liquid.

The mixing or expansion chamber 76 has cross sectional area that is significantly larger the portions of the first and second fluid passageways which feed into it. The mixing chamber 76 may be any of the shapes disclosed in International patent application published as WO 2005/005055 A1 or International patent application No. GB2005/004415, for example.

The nozzle arrangement 18 may include any of the flow control means disclosed in the applicant's International patent application published as WO 01/89958 A1. It is an important aspect of the present invention that the air is mixed with the liquid before the liquid enters the swirl chamber 116 or any other control features that may be incorporated in the nozzle 18.

The pre-compression valves 80, 180 can be set to open at any desired value, which is typically in the range 0.5 to 10 bar. However, for most applications it is expected that the pre-compression valves will open at a pressure in the range 2 to 4 bar.

Where the dispenser is configured to dispense a liquid as foam, the nozzle will omit the spray features but may include a filter to help improve the quality of the foam. In this arrangement, mixing air with the liquid will also improve the quality of the foam.

The second embodiment of the pump engine 14 can be modified in various ways. Thus the rolling diaphragm 168 could be replaced by a flexible dome arrangement similar to the dome 70 and either or both of the rolling diaphragm 168 and the flexible dome 70 could be replaced by a flexible bellows arrangement. The design of the various valves can also be modified as will be understood by those skilled in the art.

It can be seen, that the various aspects of the invention provide a dispenser that is simple in design and easy to manufacture whilst being reliable and effective in operation. The dispenser engine can be manufactured from as few as two separate moulded components that can be readily assembled. The design of the dispenser means that the components can be moulded easily using bi-injection moulding techniques with no or only limited side action. In many applications, the main, relatively rigid components will be moulded from polypropylene whilst the flexible over moulding would then be a compatible plastic such as neoprene, for example.

By providing the main working components of the dispenser as an engine or unit to which a separate casing is mounted, dispensers can be produced with a variety of different looking casings but using the same engine. This allows for greater product choice but reduces the overall cost of manufacture. The engine may be permanently fixed in the casing and the fluid storage chamber refilled as required. Alternatively, the whole dispenser can simply be thrown away when the liquid chamber is empty. As a further alternative, the engine may be removable from the casing, in which case, replacement engines can be supplied as refill units for customers. For example, if the dispenser is used to dispense an air freshener, a range of perfumes can be offered. Alternatively, where the dispenser is used to dispense a medication, the engines may be supplied through pharmacists so that use of the medication can be regulated.

In the embodiments described, the casing 12 completely encases the engine 14. However, this need not be the case particularly where, as in the second embodiment, one member of the engine is formed entirely of a rigid material. In this arrangement especially, the outer face of the rigid base member 48 can provide an outer surface of the dispenser. The casing 12 need then only be positioned over the cover member 50 so as to encase the flexible components. The casing 12 may also comprise an integral trigger or actuator member. Whilst this does not provide the same degree of flexibility in changing the overall appearance of the dispenser, it is less costly than using a complete outer casing.

Whilst it is advantageous that the fluid storage chamber 16 is formed between a rigid wall portion 52 and a flexible wall portion 54 which conforms closely to the rigid wall portion, it will be appreciated that in a dispenser in accordance with some aspects of the invention this arrangement sis not essential. Thus the flexible wall portion 54 could be configured to be spaced from the rigid wall portion 52 when the fluid storage chamber is empty, in a manner similar to a conventional fluid store. In this case a dip tube will be required so that fluid from the storage chamber 16 can be introduced into the liquid pump chamber in a conventional manner. Indeed the fluid storage chamber n this case could be provided by means of a generally rigid container or between two rigid wall portions.

Although the various aspects of the invention have been described above in combination in a single dispenser, it will be appreciated that each aspect of the invention can be used independently of the others.

Whereas the invention has been described in relation to what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not limited to the disclosed arrangements but rather is intended to cover various modifications and equivalent constructions included within the spirit and scope of the invention.

Where the terms “comprise”, “comprises”, “comprised” or “comprising” are used in this specification, they are to be interpreted as specifying the presence of the stated features, integers, steps or components referred to, but not to preclude the presence or addition of one or more other feature, integer, step, component or group thereof. 

1. A pump engine for pump-action fluid dispenser, the engine comprising a fluid storage chamber, a fluid outlet and a manually actuated pump means for delivering fluid from the fluid storage chamber to the outlet under pressure, the engine having a body comprising two parts which define between them the fluid storage chamber and least one pump chamber of the pump means, characterised in that the fluid storage chamber is defined between opposing wall portions of the two parts of the body and in that at least one of the opposing wall portions is flexible and is configured to conform closely to the contour of the other of the opposing wall portions, at least when the fluid storage chamber is empty.
 2. A pump engine as claimed in claim 1, in which the other of the opposing wall portions is rigid.
 3. A pump engine as claimed in claim 2, in which the rigid opposing wall portion has an inner surface which is generally concave.
 4. A pump engine as claimed in any one of the preceding claims, in which the flexible wall portion is resiliently biased to conform closely to the contour of the other of the opposing wall portions.
 5. A pump engine as claimed in any one of the preceding claims, in which the fluid storage chamber has an inlet through which fluid can be introduced into the chamber.
 6. A pump engine as claimed in claim 5, in which the inlet has a closure means that can be removed to allow the chamber to be refilled.
 7. A pump engine as claimed in any one of the preceding claims, in which the pump comprises a first pump chamber having an inlet fluidly connected to the fluid storage chamber through which a first fluid in the fluid storage chamber can enter the first pump chamber, and an outlet fluidly connected by means of a first fluid passage means to the fluid outlet, the pump further comprising one way valve means configured to permit fluid to enter the first chamber through the inlet from the fluid storage chamber only when the pressure in the first pump chamber is at a predetermined threshold value that is lower than the pressure of the first fluid in the fluid storage chamber and an outlet pre-compression valve means configured to permit fluid to pass from the first pump chamber through the first fluid passage means to the fluid outlet only when the fluid in the chamber is at or above a predetermined threshold value.
 8. A pump engine as claimed in claim 7, in which the pump further comprises a second pump chamber for delivering a second fluid to the fluid outlet under pressure and having an inlet means through which the second fluid can enter the second pump chamber from a second fluid source, the inlet having a one way valve means arranged to permit fluid from the second fluid source to enter the second fluid chamber only when the pressure within the second chamber is below that of the fluid in the second fluid source and an outlet fluidly connected to fluid outlet by means of a second fluid passage means, the pump engine further comprising a second fluid pre-compression valve arranged to permit the second fluid to flow from the second pump chamber through the second passage means only when the second fluid in the second chamber is at, or above, a predetermined minimum value.
 9. A pump engine as claimed in claim 8, in which the second fluid source comprises a further fluid storage chamber in the engine.
 10. A pump engine as claimed in claim 9, in which the further fluid storage chamber is defined between opposing wall portions of the two parts of the body, at least one of the opposing wall portions being flexible and configured to conform closely to the other of the opposing wall portions, at least when the further fluid storage chamber is empty.
 11. A pump engine as claimed in claim 8, in which the second fluid is air and the second pump chamber inlet is configured to enable ambient air to be drawn into the second pump chamber when the pressure inside the second pump chamber is at or below the ambient air pressure.
 12. A pump engine as claimed in claim 11, in which the first fluid is a liquid and the first fluid passage includes a mixing chamber, the second fluid passage means fluidly connecting the outlet of the second pump chamber with the mixing chamber, the engine further comprising a third fluid passage means which fluidly connects the outlet of the second pump chamber with the first passage means at a position upstream from the mixing chamber, the arrangement being such that in use, the air flowing from the second chamber is divided into two portions, one portion flowing through the second fluid passage means directly into the mixing chamber to mix with the liquid flowing from the first pump chamber, and a second portion, which flows through the third fluid passage means into the first passage to assist in driving the liquid along the first fluid passage means into the mixing chamber.
 13. A pump engine as claimed in claim 12, in which the first fluid passage means comprises a pre-compression chamber immediately downstream of the first pump chamber outlet pre-compression valve, and the third fluid passage means fluidly connects the outlet of the second pump chamber with the first pump chamber outlet pre-compression chamber.
 14. A pump engine as claimed in any one of claims 7 to 13, in which the first pump chamber is defined between a flexible member and a rigid wall portion of the engine, the flexible member being compressible towards the rigid wall portion to pressurise the fluid in the first chamber.
 15. A pump engine as claimed in claim 14, in which the flexible member is a dome-shaped member
 16. A pump engine as claimed in any one of claims 7 to 15, in which the second pump chamber is defined in part by means of a further flexible member which can be compressed or distorted to reduce the volume of the second chamber so as to pressurise the fluid inside the second chamber.
 17. A pump engine as claimed in claim 16, in which the further flexible member is a rolling diaphragm.
 18. A pump engine consisting of two members that are assembled together to form the engine.
 19. A pump engine as claimed in claim 18, in which one of the members comprises a rigid frame to which all the flexible components of the engine are mounted.
 20. A pump engine as claimed in claim 19, in which the other of the members is formed entirely of a substantially rigid material.
 21. A pump engine as claimed in claim 19, in which said one of the members is formed from two or more plastics materials using bi-injection moulding techniques.
 22. A pump engine as claimed in any one of claims 18 to 21, in which the two members are moulded as a single integral component with the two members joined to one another by flexible hinge means so that they can be moved relative to one another for assembly.
 23. A pump engine as claimed in any one of claims 18 to 22, in which the two members are permanently fixed together in the assembled condition by welding.
 24. A pump engine as claimed in any one of the preceding claims, in which the final outlet comprises an outlet nozzle and the dispenser is configured to dispense a liquid as an atomised spray.
 25. A pump engine as claimed in any one of the preceding claims, configured to dispense a set dose of fluid on each actuation of the pump.
 26. A pump-action dispenser comprising an engine as claimed in any one of the preceding claims, the dispenser further comprising an actuator member to which a user can apply a force to actuate the pump means.
 27. A pump-action dispenser as claimed in claim 26, comprising a pump engine as claimed in claim 14 and claim 16, in which the actuator member is configured to engage and compress the flexible member and the further flexible member when a force is applied by a user.
 28. A pump-action dispenser as claimed in claim 27, in which the first and second pump chambers are laterally spaced from one another, the actuator member having two abutment means configured so that when a force is applied by a user, a first one of the abutment means contacts and compresses the flexible member defining the first pump chamber and a second one of the abutment means contacts and compresses the flexible member defining the second pump chamber.
 29. A pump-action dispenser as claimed in claim 28, in which the dispenser is configured so that the second abutment means contacts and compresses the flexible member defining the second pump chamber to pressurise the fluid in the second chamber before first abutment means contacts and compresses the flexible member defining the first pump chamber.
 30. A pump-action dispenser as claimed in claim 28 or claim 29, configured so that, in use when a user applies a force to the actuator member, the flexible member defining the second pump chamber continues to be compressed for a short period after the flexible member defining the first pump chamber is fully compressed.
 31. A pump-action dispenser as claimed in claim 30, in which the actuator member is configured to rock, tilt, deform or distort after the flexible member defining the first pump chamber has been fully compressed so as to continue compressing the flexible member defining the second pump chamber.
 32. A pump-action dispenser as claimed in any one of claims 26 to 31, in which the actuator is formed integrally with or mounted to the engine.
 33. A pump-action dispenser comprising a pump engine as claimed in any one of claims 1 to 25 and an outer casing which covers at least part of the engine.
 34. A pump-action dispenser as claimed in claim 33, in which the outer casing completely encases the pump engine and comprises an opening which corresponds with the fluid outlet of the engine.
 35. A pump-action dispenser as claimed in claim 33 or claim 34, in which the engine is removably mounted in the outer casing.
 36. A pump-action dispenser as claimed in claim 35, in which the engine can be removed from the outer casing and replaced by a similar engine.
 37. A pump-action dispenser as claimed in any one of claims 33 to 36 and any one of claims 26 to 31, in which the actuator comprises part of the outer casing.
 38. A pump-action dispenser as claimed in claim 37, in which the actuator member comprises an integral part of a wall portion of the outer casing and is attached to the wall portion by means of a flexible hinge.
 39. A fluid container for a pump-action dispenser, the container having a chamber for receiving a fluid to be dispensed, characterised in that the chamber is defined between a rigid wall portion of the container and a flexible wall portion of the container that is configured to conform closely to the contour of the rigid wall portion, at least when the container is empty.
 40. A fluid container as claimed in claim 39, in which the flexible wall portion is resiliently biased to conform closely to the contour of the rigid wall portion.
 41. A fluid container claimed in claim 39 or claim 40, in which the inner surface of the rigid wall portion defines a generally concave recess.
 42. A pump-action dispenser having a fluid container as claimed in any one of claims 39 to
 41. 43. A pump-action fluid dispenser, the dispenser comprising a pump chamber at least partly defined by a flexibly resilient rolling diaphragm.
 44. A pump-action fluid dispenser as claimed in claim 43, in which the pump chamber is defined between the rolling diaphragm and a rigid wall portion.
 45. A pump-action fluid dispenser comprising an outlet nozzle, a first pump chamber for pressurising a liquid to be dispensed, a second pump chamber for pressurising air, a first fluid passage means for fluidly connecting the first chamber to the outlet nozzle, a second fluid passage means for fluidly connecting the second pump chamber to a mixing chamber forming part of the first passage means; characterised in that the dispenser further comprises a third fluid passage means for connecting the second chamber to the first fluid passage means at a position upstream from the mixing chamber.
 46. A pump-action fluid dispenser as claimed in claim 45, in which the mixing chamber is an expansion chamber having a cross sectional area larger than that of the fluid passageways leading into it and is located upstream of the outlet nozzle.
 47. A pump-action fluid dispenser as claimed in claim 45 or claim 46, in which the dispenser is configured to dispense the liquid in the form of an atomised spray and the outlet nozzle comprises one or more control means configured to affect the quality of the spray.
 48. A pump-action fluid dispenser as claimed in claim 47, in which the control means comprises one or more selected from the following group: a swirl chamber; an expansion chamber; an inner orifice configured to generate a spray or jet of the liquid inside the nozzle; a dog leg; or multiple flow passageways.
 49. A pump-action fluid dispenser comprising an outlet nozzle, a first pump chamber for pressurising a liquid to be dispensed, a second pump chamber for pressurising air, a first fluid passage means for fluidly connecting the first chamber to the outlet nozzle, a second fluid passage means for fluidly connecting the second pump chamber to a mixing chamber forming part of the first passage means, characterised in that the dispenser is configured such that during use when the pump is actuated, pressurised air from the second pump chamber enters the mixing chamber through the second fluid passage means before liquid from the first pump chamber enters the mixing chamber through the first fluid passage means.
 50. A pump-action fluid dispenser as claimed in claim 49, in which the dispenser is configured such that, during use when the pump is actuated, air from the second pump chamber continues to enter the mixing chamber for a short period of time after the liquid from the first pump chamber has stopped flowing into the mixing chamber.
 51. A pump-action dispenser as claimed in claim 49 or claim 50, in which the dispenser comprises a third fluid passage means for connecting the second chamber to the first fluid passage means at a position upstream from the mixing chamber.
 52. A pump-action dispenser as claimed in any one of claims 49 to 51, in which the mixing chamber is positioned immediately upstream of an outlet nozzle arrangement.
 53. A pump-action fluid dispenser comprising a manually actuated pump having a first pump chamber defined in part by a first flexible member which can be distorted from an initial configuration to a second configuration in order to reduce the volume of the first chamber and evacuate a fluid from the first chamber and a second pump chamber laterally spaced from the first, the second pump chamber being defined in part by a second flexible member which can be distorted from an initial configuration to a second configuration in order to reduce the volume of the second chamber and evacuate a fluid from the second chamber, characterised in that the dispenser further comprises an actuator member configured to engage and distort the first and second flexible members when a force is applied by a user to actuate the pulp means; characterised in that the actuator member is configured to rock, tilt, deform or distort in order to fully evacuate both chambers.
 54. A pump-action dispenser as claimed in claim 53, in which the actuator member has a first, free end and a second end which is mounted to a support by means of a flexible hinge, the actuator member or lever being configured to rock, tilt, deform or distort at a position between the two ends in order to fully evacuate both chambers.
 55. A pump-action dispenser as claimed in claim 53 or claim 54, in which the actuator member has two abutment means configured so that when a force is applied by a user, a first one of the abutment means contacts and distorts the first flexible member and a second one of the abutment means contacts and distorts the second flexible member.
 56. A pump-action dispenser as claimed in claim 54 or claim 55, in which the dispenser is configured so that, in use when a user applies a force to the actuator member to actuate the pump means, the second abutment means contacts and distorts the second flexible member before first abutment means contacts and distorts the first flexible member.
 57. A pump-action dispenser as claimed in any one of claims 53 to 56, configured so that, in use when a user applies a force to the actuator member to actuate the pump means, the first pump chamber is fully evacuated before the second pump chamber.
 58. A pump-action dispenser as claimed in any one of claims 55 to 57 when dependent on claim 54, in which the first abutment is positioned between the second abutment and the hinge and the actuator member is configured to rock, tilt, deform or distort about the first abutment member.
 59. A pump-action dispenser comprising a pump unit having an outlet nozzle, a fluid storage chamber and a manually actuated pump means for delivering a fluid from the fluid storage chamber to the outlet nozzle, characterised in that the dispenser further comprises a separate casing which at least partially encases the pump unit.
 60. A pump-action dispenser as claimed in claim 59, in which the casing completely encases the pump unit.
 61. A pump-action dispenser as claimed in claim 59 or claim 60, in which the casing is separable from the pump unit, so that the pump unit can be replaced by a similar pump unit.
 62. A pump-action dispenser as claimed in any one of claims 59 to 61, in which the casing comprises an actuator member to which a user can apply a force to actuate the pump.
 63. A fluid dispenser substantially as herein before described with reference to and as illustrated in FIGS. 1 to 9 or FIGS. 10 and 11 or FIGS. 12 to 15 of the accompanying drawings. 